ASTM B912 Electropolishing Standard for Stainless Steel Alloys

Able Electropolishing meets the high standards of the American Society for Testing and Materials (ASTM), including the ASTM B912 for electropolishing stainless steel.

What Is ASTM B912 Electropolishing?

The ASTM B912 electropolishing specification outlines the electropolishing process for stainless steel alloys. This type of stainless steel passivation includes 200, 300 and 400-series alloys and is superior to standard chemical passivation.

For a metal finisher to meet these standards for stainless steel passivation, they must adhere to specific protocols and ensure a particular quality of work. According to the ASTM, the electropolisher must include post-coating procedures as part of the process, as well as performance testing by means such as a salt spray test, a humidity test or a copper sulfate test. These factors and others determine eligibility for meeting this specification.

Electropolishing vs. Passivation

Electropolishing Before & After

While passivation is useful for removing free iron and contaminants from stainless steel and is more well known, electropolishing is often a better option and can be used on far more metal alloys.

Electropolishing removes a microscopically precise layer of surface material, to tolerances as low as +/-.0001″, depending on the alloy. This degree of precision and consistency, along with the ability to remove a variety of surface imperfections in one process, is why electropolishing is so often specified for critical parts used in medical implants and surgical instruments, aerospace components and fragile or critical parts used in other industries. Electropolishing is a one-stop process for a micro-smooth, ultraclean, corrosion and pathogen-resistant surface finish – with 30 times more corrosion resistance than passivation.

Electropolishing also eliminates the need for additional metal finishing processes like hand deburring, tumbling, pickling, and cleaning.

Learn more >

Contact us to learn more about electropolishing